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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
Advanced Search

To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

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subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

32494 results found.

  1. GRB 050713A : Swift-BAT Refined Analysis
  2. GRB050712: Swift UVOT Observation of Afterglow Emission
  3. GRB 050713A XMM-Newton observation
  4. GRB 050713b : Lulin R-band observations
  5. GRB050713B: Faulkes North Telescope observation
  6. RBO RI observations of GRB 050713A
  7. GRB050709 : Chandra source optical counterpart
  8. GRB050713: Liverpool Telescope prompt observations
  9. GRB 050712, optical observations
  10. GRB050709: Candidate X-ray Afterglow from Chandra
  11. GRB 050713: ARC NIR Detections and Identification of Fading
  12. GRB050713: possible I-band afterglow
  13. GRB 050713A: ROTSE-III Optical Limits
  14. GRB050712: XRT refined analysis
  15. GRB050709: Radio Observations
  16. GRB 050709: Swift UVOT and XRT observations
  17. GRB 050712: Swift-BAT Refined Analysis
  18. GRB050712: UVOT candidate optical counterpart
  19. GRB 050712: Swift XRT afterglow position
  20. GRB 050709: LCO40 Observations
  21. GRB050709, optical observations
  22. GRB050709: A Possible Short-Hard GRB Localized by HETE
  23. GRB 050525a: PROMPT VRcIc Detections
  24. GRB 050525a: ARC 3.5-meter Optical and NIR Observations
  25. GRB 050626 optical observations
  26. GRB 050701
  27. GRB 050701, optical observations
  28. GRB 050408: ARC 3.5-meter NIR Observations
  29. GRB 050701: Refined XRT analysis
  30. Swift UVOT observations of GRB 050701
  31. GRB050701: Swift-BAT Refined analysis
  32. GRB 050701: Swift XRT afterglow position
  33. GRB 050607, radio observations
  34. H11603: An X-ray flare from V4641 Sgr, or a possible XRF
  35. GRB 050626 - Correction to GCN 3552
  36. GRB 050626 - a long GRB detected with INTEGRAL
  37. GRB 050525A: Swift Late-Time Decay Rate
  38. GRB050525a: HST Observations
  39. CORRECTION: GRB050603 Swift UVOT Afterglow Observations
  40. H3800 and H3801 on 2005 June 11: two bursts from SGR1806-20 localized by HETE
  41. XRF 050509c: Optical monitoring
  42. XRF050509c: Radio Detection
  43. GRB 050416(a): Host Galaxy Redshift Determination
  44. GRB 050607: MDM Observation
  45. GRB 050607: RTT150 optical observations
  46. GRB050607: refined analysis of prompt REM observations
  47. Swift/UVOT observations of GRB050607
  48. GRB 050607 : Lulin R-band observation
  49. GRB 050607: PROMPT VRcIc Observations
  50. GRB 050607: RAPTOR-S Early Optical Limits
  51. GRB050607: KAIT optical limits
  52. GRB 050525a, Mid-Infrared Observations
  53. GRB 050607: MDM Observations
  54. GRB050607,optical observation
  55. GRB 050607 - XRT refined data analysis
  56. GRB 050603: prediction of t_break
  57. Limits on a SN in the field of GRB 050509b
  58. GRB 050603: Redshift
  59. GRB 050603 - XRT data analysis of the first day
  60. Konus-Wind observation of GRB 050603
  61. GRB 050603: Analysis of UVOT data
  62. GRB050603: Fading Afterglow observed by Swift UVOT
  63. GRB050603, submillimetre observations
  64. GRB 050603: Swift XRT Position
  65. GRB050603: Radio Detection
  66. GRB 050603: Swift-BAT refined analysis of a long three-spiked burst
  67. GRB 050603: Afterglow Identification from LCO
  68. GRB 050603: INTEGRAL shows it is not a short GRB
  69. GRB 050408: jet break in the XRT light curve
  70. GRB 050525a, infrared observations
  71. GRB 050525a, SMARTS optical/IR afterglow observations
  72. Correction to GCN Circ 3502 on GRB 050528
  73. Swift-BAT GRB 050528: a soft burst
  74. Update on Swift-BAT GRB 050528 (Trigger 130679)
  75. GRB050528: BOOTES optical candidate (retraction)
  76. GRB050504: Ashra-P2/3 monitor and Ashra-AFT response
  77. GRB050525a: Radio Observations
  78. GRB 050509b: refined XRT/Chandra afterglow position analysis
  79. GRB050525a: optical upper limits
  80. GRB 050525a: SARA Observations
  81. GRB 050525B: Swift-BAT observations
  82. GRB 050525: MITSuME Optical Observation in VRI
  83. GRB 050525a: MDM Observations
  84. GRB050525A,optical observation
  85. GRB 050525 : Lulin optical afterglow observations
  86. GRB050525: Super-LOTIS observations
  87. GRB 050525, spectral lag pseudo-redshift
  88. GRB 050525a: Gemini/GMOS Spectra
  89. GRB050306: optical afterglow not confirmed
  90. GRB 050525: BART optical observation
  91. GRB 050525A: BOOTES simultaneous optical observations
  92. GRB 050525A: Swift-BAT refined analysis
  93. GRB050525: Optical observations
  94. GRB 050525B: INTEGRAL shows it is unrelated to GRB050525A
  95. Swift/UVOT UV and optical detections of GRB 050525
  96. Konus-Wind observation of GRB 050525
  97. GRB 050525: TAROT observations of the early afterglow
  98. INTEGRAL detection of GRB 050525
  99. GRB 050525, infrared observations
  100. GRB 050525: Optical observation

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